Certain types of aircraft such a commercial fixed wing aircraft and rotorcraft such as, for example, helicopter-type aircraft, are required by federal regulatory agencies to carry inflatable floatation devices for passenger safety in the event of an emergency while flying over water. In the rotorcrafts, floatation devices and systems have also been employed in order to enable the craft to land on water in emergency situations, when, for example, the rotorcraft loses power. Such systems provide passengers with extra critical time before the rotorcraft sinks. Such emergency floatation systems typically include multiple emergency floatation devices mounted to the rotorcraft landing gear.
Various prior art floatation devices have been used to support vehicles such as a helicopter on a water surface. Early float assemblies include cylindrical shaped float tubes which are inflatable through the use of compressed air and controlled by the pilot. A float is attached to each skid of the helicopter allowing the craft to land and for the occupants to evacuate, and in some cases, rescue the helicopter as well.
Helicopters flying over water typically also carry a life-raft. Before exiting the aircraft, the crew must locate and remove the inflatable rafts. After exiting the aircraft, the rafts are inflated. In case of an emergency water landing, it is typical for the pilot to initially activate the floats, land on water, and then to deploy the life-raft where the passengers wait until rescued.
The life-raft is typically stored on the rear seat of the aircraft. The internally stowed inflatable rafts must be located, removed, and activated by the crew, taking precious time during an emergency situation. A further complication is that helicopters typically have only three rear seats for passengers and one of these seats must be filled with the life-raft. Safety regulations dictate that nothing may be placed under the seats. Further, the raft cannot be stowed in a luggage compartment because it must be readily accessible when egressing in an emergency.
Positioning of the inflatable raft outside of the helicopter or rotorcraft eliminates the necessity of manually ejecting the raft from the interior of the craft prior to the required inflation. This avoids major difficulties which might exist during the emergency situations and saves valuable time.
An external life-raft and floatation device combination applicable for use with rotorcraft is known in the art and has been disclosed by U.S. patent is U.S. Pat. No. 6,709,305. However, the device of this patent is limited because the life-raft forms an inseparable combination within the floatation device itself. Since the raft is contained inside the float pack, the float must be inflated first followed by the deployment of the raft. This is a substantial drawback of this prior art device and can be clearly seen when a pilot inadvertently inflates the life-raft first, thus possibly preventing deployment of the float and damaging to the system. In the context of an emergency landing, this limitation of the prior art design can be costly to the rescue efforts of the survivors and the helicopter. Furthermore, this prior art arrangement virtually prevents independent deployment of the life-raft without actuation of the respective floats. By way of example, the ability to deploy the raft without activation of the floats is important when making an emergency landing on an unstable oil rig or platforms where the floats are not necessary but the life-rafts are often needed. Another substantial drawback of the emergency evacuation device of U.S. Pat. No. 6,709,305 is that it provides an inseparable and prepackaged arrangement combining the float and the life-raft. Thus, it cannot be readily utilized for retrofitting an existing float system by adding a life-raft module.
In view of the above, it has been a long felt unsolved need to provide an external floatation device system for a rotorcraft, where the life-raft and floatation device can be operated independently from each other. There is also a need for a life-raft module which can be used for retrofitting an existing float system, so as to eliminate the necessity of providing a rotorcraft with a new and costly float system. Thus, the system of the invention provides a pilot with maximum available options to cover more eventualities in the event of an emergency rotorcraft landing. It is an essential feature of the invention that the life-raft can be deployed without the floats, and the floats can be activated without deployment of the life-rafts.